NOVATEUR PUBLICATIONS International Journal Of Research Publications In Engineering And Technology [IJRPET] ISSN: 2454-7875 VOLUME 2, ISSUE 8, Aug. -2016
SIMULATION OF GRID INTEGRATED WIND ENERGY CONVERSION SYSTEM UMESH M. BARHATE Department of electrical engineering DR. B. A. T. U. Lonere, Raigad, India-402103 DR. P. K. KATTI Department of electrical engineering
ABSTRACT: One of the primary needs for socio-economic development in any nation in the world is the reliable electricity supply system. Renewable energy technologies offers clean, abundant energy gathered from self-renewing resources such as the sun, wind etc. As the power demand increases, power failure also increases. So, renewable energy sources can be used to provide constant loads. Wind energy is expected to be one of the most prominent sources of electrical energy in years to come. In this paper wind energy conversion system is integrated with the grid. Wind turbines are packaged systems that include a rotor, a generator, turbine blades, a drive and coupling blades. This process reveals a unique step in electricity generation and availability from natural resources without hampering the ecological balance. The goal of this paper to build a complete model of integrated wind energy conversion system with grid in MATLAB/Simulink. KEY-WORDS: Socio-economic, Wind energy, MATLAB/ Simulink, integrated generation INTRODUCTION: Recent developments and trends in the electric power consumption indicate an increasing use of renewable energy resources (RES). Maximum energy demand is supplied by the burning of fossil fuels. Hence increasing air pollution, global warming, diminishing fossil fuels and their increasing cost have made it necessary to look towards RES as a future energy solution.[2] Solar energy and wind energy is clean, inexhaustible, unlimited, and environmental friendly. Such characteristics have attracted the energy sector to use renewable energy sources on a larger scale. However, all renewable energy sources have drawbacks. Wind is dependent on unpredictable factors such as weather and climatic conditions. Wind power is another most competitive renewable technology and, in developed countries with good wind resources, onshore wind is often competitive with fossil fuel fired generation. Wind power generation has experienced a tremendous growth in the past decade,
and has been recognized as an environmental friendly and economically competitive means of electric power generation.[5] The wind energy system generates power in the form of AC with different voltage and frequency levels in case of variable speed operation. In this paper wind energy conversion system is simulated using MATLAB. Output of this system is connected to the grid through point of common coupling (PCC). WIND ENERGY SYSTEM: Wind power systems convert the kinetic energy of the wind into other forms of energy such as electricity. Although wind energy conversion is relatively simple in concept, turbine design can be quite complex. Most commercially available wind turbine uses a horizontal – axis configuration with two or three blades, a drive train including a gearbox and a generator and a tower to support the rotor.[6] The power available in the wind is proportional to the cube of its speed. This means that if wind speed doubles, the power available to the wind generator increases by a factor of 8 (2 x 2 x 2 = 8) Since wind speed increases with height increases to the tower height can mean enormous increases in the amount of electricity generated by a wind turbine.
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Figure 1. Proposed system of grid interconnection of RES
NOVATEUR PUBLICATIONS International Journal Of Research Publications In Engineering And Technology [IJRPET] ISSN: 2454-7875 VOLUME 2, ISSUE 8, Aug. -2016 POWER CONTAINED IN WIND: Wind is natural phenomenon related to movement of air masses caused primarily by the differential solar heating of the earth’s surface. The wind turbine captures the winds kinetic energy in a rotor consisting of two or more blades mechanically coupled to an electrical generator. The amount of power transferred to a wind turbine is directly proportional to the area swept out by the rotor, to the density of the air, and the cube of the wind speed.[7] The power P in the wind is given by, P = ½ Cp. ρ.A. V3(1) Where Cp is the turbine power coefficient. A theoretical maximum value of 0.593 has been proposed for Cp ρ = air density (kg/m3), A is the rotor swept area (m2) PROPOSED WIND SYSTEM: In proposed wind power system turbine, permanent magnet synchronous generator (PMSG) is used. The main advantages of PMSG are less maintenance, high efficiency, high power factor operation, eliminates DC link excitation circuit thus reduces its complications. Output of system is AC and directly fed to the PCC through a circuit breaker. The grid is also connected to PCC and load is supplied from the PCC. Applications of Wind Power System are listed below: i) Remote and rural village electrification. ii) Residential colonies & apartments for general lighting. iii) Integration with photo voltaic system.
Figure2. Simulation model of wind turbine SIMULATION MODELS: SIMULINK MODEL OF WIND TURBINE: Turbine is main part of wind generation system. Aerodynamic design of turbines coverts the wind energy into the mechanical power. This mechanical power is delivered to the rotor of synchronous generator which coverts it into the electrical form. Output of this system is AC and fed to grid through (PCC).Simulink model of wind turbine
With the use of renewable energy based system the emission of carbon and other harmful gases are reduced to approximately 80% to 90% in environments. Figure. 2 shows the simulation model of wind turbine.
Figure 3. Simulation model of wind turbine system
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NOVATEUR PUBLICATIONS International Journal Of Research Publications In Engineering And Technology [IJRPET] ISSN: 2454-7875 VOLUME 2, ISSUE 8, Aug. -2016 SIMULINK MODEL OF WIND TURBINE SUBSYTEM:
Θ is Rotor angular position and Tm is Shaft mechanical torque. RESULTS:
(a)
(b) Figure 4 simulation model of hybrid system PERMANENT MAGNET SYNSCHRONOUS GENERATOR:
Figure 5 waveform of (a) Electromagnetic torque vs time (b) Mechanical torque vs time
The wind energy conversion system drives a high speed PMSG for conversation of mechanical energy to electrical energy.[8] The PMSM model used is a 2 pole with a non-salient rotor. The dynamic equations of PMSM expressed in the rotor reference frame (dq frame) a follow: ELECTRICAL EQUATIONS : d dt d dt
id = iq =
1 Ld 1 Lq
vd − vq −
R Ld L Lq
id + iq −
Lq Ld Ld Lq
(a)
(2)
pωr iq pωr id −⋋
pω r
(3)
Lq
Te = 1.5 p(⋋ iq + Ld − Lq idiq)
(4)
(b)
MECHANICAL EQUATION : d dt d dt
ωr =
1 J
θ = ωr
(Te − Fωr − Tm)
(5) (6)
where, Lq and Ld are q and d axis inductances, iq and id are q and d axis currents, R is Resistance of the stator windings, vq & vd are q and d axis voltages, ωr is Angular velocity of the rotor, λ is Flux induced by the permanent magnets in the stator windings, P is Number of pole pairs, Te is Electromagnetic torque, J is combined inertia of rotor and load, F is Combined viscous friction of rotor and load,
© Figure 6waveform of (a) Time vs. Wind speed (b) Rotor speed vs. time (c) Pitch angle vs. time
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NOVATEUR PUBLICATIONS International Journal Of Research Publications In Engineering And Technology [IJRPET] ISSN: 2454-7875 VOLUME 2, ISSUE 8, Aug. -2016 [3] Yvonne Coughlan, Paul Smith, Alan Mullane, Member, IEEE and Mark OMalley, ― Wind Turbine Modelling for Power SystemStability Analysis –A system operator Perspective‖, IEEE Transaction on Power System, Vol. 23, No. 3, pp. 345-375, August 2007. [4] Sandeep Kumar, Vijay Kumar Garg - A HYBRID MODEL OF SOLAR-WINDPOWER GENERATION SYSTEM, IJAREEIE volume 2, issue 8, august 2013. [5] T. Ackermann and V. Knyazkin. Interaction between distributed generation and the distribution network: operation aspects. In Transmission and Distribution Conference and Exhibition2002: Asia Pacific. IEEE/PES, volume 2, pages 1357–1362, Oct 2002. [6] T. Ackermann. Wind Power in Power Systems. Joh Wiley & Sons, Ltd, Royal Instate of Technology, Stockholm Sweden, 2005. [7] J.G. Slootweg. Wind Power: Modelling and Impact on Power System Dynamics. PhD thesis, Technische Universiteit Delft, Delft, Netherlands, December 2003. [8] S. Heier. Grid Integration of Wind Energy Conversion Systems. John Wiley & Sons, Ltd, Chicester, UK, 1998.
(a)
(b)
(c) Figure 7 waveform of (a) Phase voltage vs time, (b) Line current vs time (c) Phase voltage(rms) vs time CONCLUSION: The use of wind power generation is an especially vivid and relevant choice for students of electrical technology as it is a power source of technological, political, and economic importance in country. This technique has lower overhead and finds applications in remote space power generation, energy conversion systems and rural electrification. Relatively small power generations such as small wind or solar system, would be an approach to penetrate renewable to the power systems. Small renewable energy sources are connected to the low side of the distribution systems. The proposed system is employed by using MATLAB/ SIMULINK to model the wind power, turbine and therefore planned the system. REFERENCES: [1] J. Bhagwan Reddey, D.N. Reddy ―Probablistic Performance Assessment of a Roof Top Wind, Solar Photo Voltaic Hybrid Energy System‖, Engineering Science and Education Journal, Vol. 2, No. 4, pp. 281298, February 2008. [2] Stanley R. Bull, ―Renewable Energy Today and Tomorrow‖, Proceedings of the IEEE, vol. 89, no. 8, pp. 316-381, August 2001.
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